In the relevant mining/dressing technology, ore is understood to mean metalliferous rock from which the metalliferous components are to be separated as recoverable materials. Especially in the case of copper ores, the recoverable materials are in particular sulfide copper materials which are to be enriched, for example—but not exclusively—Cu2S. The Cu-free rock surrounding the material grains is referred to as matrix rock or gangue, among experts after grinding of the rock also as tailing or hereinafter for short as sand.
According to typical conventional methods for ore separation are already known which can be performed continuously if necessary. However, these methods mainly operate according to the principle of mechanical flotation, wherein the ground rock is mixed with water in order to be able to process it further. This mixture of water and rock flour is also referred to as pulp. The rich ore particles contained in the pre-ground rock in the pulp are first selectively given a hydrophobic coating with the aid of chemical additives and then concentrated into froth by bonding to bubbles. The mixture of rich ore particles, bubbles and water thus formed can then simply be carried away in the overflow of so-called flotation cells.
In typical conventional methods, to achieve a high level of extraction of the rich ore content from the rock, i.e. a high yield, several consecutive separation stages may be necessary, each of which contain their own flotation cells. However, overall this may be associated with high expenditure and, in addition, particularly high energy consumption.
Magnetically assisted ore extraction methods have also already been proposed but as discontinuously performed operations. As a result of execution as a discontinuously operating batch method, the yield and the associated efficiency may be limited, which may have an effect on costs.
Additional methods such as drum separators, for example, may operate continuously but may have only small flow rates due to the mechanical expenditure and maintenance required and may therefore be unsuitable for many of the ore extraction methods used in mining.
Further, methods for the continuous separation of non-magnetic ores using magnetic or magnetizable particles have been proposed, e.g., in the following non-prepublished German patent applications from Siemens AG: DE102008047841 and DE102008047842; as well as the published WO2009030669A2 from BASF AG.